Take this medicine only as directed. Do not take more of it, do not take it more often, and do not take it for a longer time than directed on the package label or by your doctor. To do so may increase the chance of side effects. This medicine may cause liver damage if too much is taken.

Dosing

The dose of chlorzoxazone and acetaminophen combination will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

• For oral dosage form (tablets):
  • For relieving painful, stiff muscles:
    • Adults Two tablets four times a day.
    • Children Use and dose must be determined by your doctor.

Missed dose

If you miss a dose of this medicine, take it as soon as you remember. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage

To store this medicine:

• Keep out of the reach of children.
• Store away from heat and direct light.
• Do not store this medicine in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down.
• Do not keep outdated medicine or medicine no longer needed. Be sure that any discarded medicine is out of the reach of children.

If you are taking this medicine without a prescription, carefully read and follow any precautions on the label. For chlorzoxazone and acetaminophen combination, the following should be considered:

Allergies Tell your doctor if you have ever had any unusual or allergic reaction to acetaminophen, chlorzoxazone, or aspirin. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.

Pregnancy Although studies on birth defects with chlorzoxazone or acetaminophen have not been done in pregnant women, these medicines have not been reported to cause birth defects or other problems.

Breast-feeding Chlorzoxazone and acetaminophen have not been shown to cause problems in nursing babies. However, acetaminophen passes into the breast milk in small amounts.

Children Studies on this combination medicine have been done only in adult patients, and there is no specific information about its use in children. However, chlorzoxazone and acetaminophen have been tested separately in children. In effective doses, these medicines have not been shown to cause different side effects or problems in children than they do in adults.

Older adults Many medicines have not been studied specifically in older people. Therefore, it may not be known whether they work exactly the same way they do in younger adults or if they cause different side effects or problems in older people. There is no specific information comparing use of chlorzoxazone and acetaminophen combination, or of chlorzoxazone alone, in the elderly with use in other age groups. However, acetaminophen has been tested and has not been shown to cause different side effects or problems in older people than it does in younger adults.

Other medicines Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking chlorzoxazone and acetaminophen combination, it is especially important that your health care professional know if you are taking any of the following:

• Antidepressants, tricyclic (amitriptyline [e.g., Elavil], amoxapine [e.g., Asendin], clomipramine [e.g., Anafranil], desipramine [e.g., Pertofrane], doxepin [e.g., Sinequan], imipramine [e.g., Tofranil], nortriptyline [e.g., Aventyl], protriptyline [e.g., Vivactil], trimipramine [e.g., Surmontil]) or
• Central nervous system (CNS) depressants (medicines that often cause drowsiness) These medicines may add to the effects of chlorzoxazone and increase the chance of drowsiness or other side effects

• Alcohol abuse or
• Allergies (asthma, eczema, hay fever, hives) or
• Hepatitis or other liver disease or
• Kidney disease The chance of side effects may be increased